Stonesifer, a former Microsoft executive who helped the Gateses launch a predecessor organization called Gates Learning Foundation in 1997, has for more than a decade been the person running the day-to-day operations at the Seattle mega-philanthropy.

It is now the world’s richest philanthropy with more than 500 employees, nearly $40 billion in assets, playing a leading role in areas such as global health, international development, education and other anti-poverty programs. Stonesifer, 51, is married to Michael Kinsley, a columnist for Time magazine.